Survivin exists in immunochemically distinct subcellular pools and is involved in spindle microtubule function.

摘要: Survivin is a member of the inhibitor apoptosis gene family that has been implicated in both inhibition and regulation mitosis. However, subcellular distribution survivin controversial variously described as microtubule-associated protein or chromosomal passenger protein. Here, we show antibodies directed to sequence Ala(3)-Ile(19) exclusively recognized nuclear pool segregated with nucleoplasmic proteins, but not outer matrix proteins. By immunofluorescence, localized kinetochores metaphase chromosomes, central spindle midzone at anaphase. Cys(57)-Trp(67) identified cytosolic survivin, which associated interphase microtubules, centrosomes, poles mitotic microtubules Polyclonal recognizing epitopes Ala(3)-Ile(19), Met(38)-Thr(48), Pro(47)-Phe(58) pools within same cell. A ratio approximately 1:6 for versus was obtained by quantitative fractionation. In synchronized cultures, abruptly increased mitosis, physically p34(cdc2), phosphorylated p34(cdc2) on Thr(34), vivo. contrast, began accumulate S phase, complexed Thr(34). Intracellular loading polyclonal antibody caused microtubule defects resulted formation multipolar spindles, did interfere cytokinesis. These data demonstrate although reported localizations exist cells, preponderant participates assembly bipolar spindle.